We propose label-free high-throughput detection of cells response to chemicals by merging microwell microtechnology with state-of-the-art label-free biosensing technology based on optical microresonators. Arrays of optical microbead sensors will be sealed against arrays of cells in microwells to monitor secretion of protein in response to chemicals released from a hydrogel. The platform can be operated on a conventional total-internal-reflection microscope setup. PUBLIC HEALTH RELEVANCE: Cells in microwell arrays fabricated from polyethyleneglycol polymer will be sealed against an array of optical microbead biosensors co-localized with a hydrogel array for controlled release of chemicals. Secreted apoptotic biomarkers such as caspase-3 protein will be monitored in label-free manner and in real-time in response to toxic chemicals released from the hydrogels.